1. Field of the Invention
The present patent relates to certain improvements in automatic weighing machines for food products which contribute various advantages to the function they are intended for and these advantages will be noted further on, besides others inherent to their organization and make-up.
2. Description of Related Art
Machines weighing food products are already known in which there is a relatively high number of containers, for example 10 to 14, which are fed with the products to be weighed from a single common entrance and which are unloaded onto other analogous containers on which the weighing is done; the machine may lack these latter containers, in which case the first ones are directly weighers. These known weighing machines include an electronic computer unit that performs the calculation of the possible weight combinations of the products stored in these containers and selects those containers whose sum of weight, in other words its total weight, is most approximate to the weight desired, and orders it to be unloaded on an exit transporter that is exhibited by these machines. This strategy corresponds to what is called "associative weighing," in which the product goes through various weighing points and an electronic calculator looks for a combination whose real value most closely approximates the desired nominal weight.
The applicant company itself is the owner of U.S. Pat. No. 8,700,794, which protects an automatic weighing machine for food products of the type (which in turn corresponds to U.S. Pat. No. 500,951 also granted to the applicant company) that comprises a structure or frame supporting the members of the machine, means for activating these members, means for feeding in the appropriate product, some means to weigh it, some bins to store it temporarily and equipped with means for unloading it onto means to convey it to the exit of the machine and a programming processing unit, which continually records the real weight of the product entering the machine as it is being weighed, as well as the real weight of the product which at each moment is contained by all and each one of the temporary storage bins, and when the weight of the product contained in a corresponding bin reaches a value preset by the user of the machine, the programming processing unit orders the unloading of all the units of product with this preset final weight; there are appropriate connection means between the above mentioned programming processing unit and the corresponding members of the machine, as well as conventional means of control, monitoring, safety, etc. of the machine.
The automatic weighing machine that is the object of the above mentioned U.S. Pat. No. 8,700,794 is characterized in that the means for feeding the product into the entrance of the machine, controlled by the programming processing unit, preferably comprise a hopper, a conduit and at least one endless belt, whose end empties out above a series of buckets that are opened on the top to receive the product which is unloaded from this end; these buckets are arranged in a circle and joined respectively in an overhanging manner to individual means for weighing that are aligned radially and closer to the center than the buckets themselves; these means for weighing are then connected with the programming processing unit and mounted on a horizontal revolving platform by suitable means in relation to a central vertical axis; in that the above mentioned buckets exhibit at least one of its walls that is movable, that is activated by suitable means and controlled by the programming processing unit; and in that it exhibits, below these buckets, a series of fixed bins that are open on the top to receive the corresponding product already weighed and with at least one of its walls that is movable, also activated by suitable means and controlled by the programming processing unit, to allow for the unloading of each batch of units of product with the preset final weight (with the batch being gathered in a suitable fixed bin); the unloading is performed on the means for conveying the above mentioned batches of product toward the exit of the machine.
The strategy followed by both the machine that is the object of U.S. Pat. No. 8,700,794 and that of U.S. Pat. No. 500,951 in their functioning corresponds to what is called "accumulative weighing," in which the programming processing units permanently take account of the real weights of the units of product that it is continually storing temporarily in all the bins that are exhibited by these machines for this purpose and continually combines them mathematically with the real weights of the units of product as they are being weighed. In this way, a greater production is obtained per unit of time of batches of units of products having a preset final weight (and also with a preset tolerance) and also a lesser number of rejected units is obtained in comparison with weighing machines known before the oldest U.S. Pat. No. 500,951.
The machine that is the object of U.S. Pat. No. 8,700,794 is adaptable to a very wide range of products (peppers, onions, potatoes, garlic, citrus products, Brussels sprouts, apples, nuts, green beans, and in general food products of varying sizes); and it has a high rate of production with minimum rejection, without the danger of possible damage to the product initially rejected, since this product remains in its corresponding bucket, and it also allows for greater regularity in the weight of the batches obtained, with a self-regulation of the feeding, in accord with the desired final weight of the batch of units of product to be obtained.